Ethoxylated hydrocarbyl butanediols and their disulfate derivatives as phosphate-free compositions

ABSTRACT

New compositions of matter useful in phosphate-free detergent compositions comprise the 2-hydrocarbyl-1,4-butanediol ethoxylate disulfates.

United States Patent [191 Anderson Jan. 14, 1975 ETHOXYLATED HYDROCARBYL [56] References Cited BUTANEDIOLS AND THEIR DISULFATE FOREIGN PATENTS OR APPLICATIONS DERIVATIVES A5 PHOSPHATE-FREE 6,709,714 l/l968 Netherlands 260/458 COMPOSITIONS Inventor: Robert G. Anderson, San Rafael,

Calif.

Assignee: Chevron Research Company, San

Francisco, Calif.

Filed: Feb. 10, 1969 Appl. No.: 798,162

US. Cl 260/458, 252/551, 260/546,

260/615 B, 260/635 D Int. Cl. C07c 141/02 Field of Search 260/458 OTHER PUBLICATIONS Schwartz and Perry, Surface Active Agents, (NY. 1949).

Primary ExaminerHoward T. Mars Assistant Examiner-Nicky Chan Attorney, Agent, or FirmG. F. Magdeburger; John Stoner, Jr.; J. T. Brooks [57] ABSTRACT New compositions of matter useful in phosphate-free detergent compositions comprise the 2-hydrocarbyl- 1,4-butanediol ethoxylate disulfates.

4 Claims, No Drawings ETHOXYLATED HYDROCARBYL BUTANEDIOLS AND THEIR DISULFATE DERIVATIVES AS PHOSPHATE-FREE COMPOSITIONS BACKGROUND OF THE INVENTION The present invention is concerned with the field of synthetic detergents and more particularly with novel 2-hydrocarbyl-butanedi0l ethoxylate disulfate derivatives suitable as biodegradable and phosphate-free detergent compositions.

Increased concern over water pollution has produced significant changes in household detergents. Initially, major emphasis has been placed on producing biodegradable surface-active components for detergents. The shift to linear surface-active materials, including linear alkyl benzene sulfonates (LAS) and alpha-olefin sulfonates, etc., has reduced pollution attributed to nonbiodegradability.

However, the above-mentioned surface-active materials are inadequate in terms of soil removal in the absence of phosphate builders. Increasing evidence appears to indicate that phosphates contribute to the growth of algae in the Nations streams and lakes. This alga growth poses a serious pollution threat to the maintenance of clear, good domestic water supplies.

In contrast to the problems encountered in utilizing the above-described detergent compositions, the present invention provides novel, biodegradable detergent compositions which exhibit high detergency and soilremoval ability in the absence of phosphate builders.

SUMMARY OF THE INVENTION Novel compositions of matter useful as phosphatefree detergent compositions comprise the 2-hydrocarbyl-l ,4-butanediol ethoxylate disulfates. The Z-hydrocarbyl-l,4-butanediol ethoxylate disulfates and their precursors may be represented by the formula:

R CH CH (CIi CH 0) Z CH -CH R (III-I wherein R and R, are hydrogen or saturated or unsaturated, straight-chain or branched-chain hydrocarbyl radicals containing from 0 to 35 carbon atoms. In a preferred embodiment, the hydrocarbyl radical, R is a saturated or unsaturated, straight-chain group containing from 16 to 22 carbon atoms and having primary attachment to the number two carbon atoms of the 1,4- butanediol and the sum of x and y varies from 2 to 6. More preferably, R is saturated and contains at least 18 carbon atoms.

In general, when the compounds of the present invention are formulated as detergent compositions, additional compatible ingredients may be incorporated therein to enhance their detergent properties. such ingredients may include, but are not limited to, anti-' corrosion, anti-redeposition, bleaching and sequestering agents, optical whiteners and certain organic and inorganic alkali and alkaline earth salts other than phosphate, such as inorganic sulfates, carbonates or borates and organic salts of the amino polycarboxylic acids; e.g., trisodium salt of nitrilo acetic acid, tetrasodium salt of ethylenediamine tetracetic acid, etc.

Surprisingly, the novel compounds of the present invention exhibit high detersive characteristics even in the absence of phosphate builders. In particular, formulations containing sodium or potassium sulfates as a major additive ingredient are preferred. This is quite unexpected, in view of the majority of the household heavy-duty detergent compounds which require phosphate builders to exhibit satisfactory levels of detergency.

In general, compatible ingredients other than water may be employed in amounts ranging from 60 to 900 parts and, preferably, from to 250 parts by weight per parts of hydrocarbyl butanediol ethoxylate disulfate utilized.

In addition, the detergent compositions may comprise from-O to 700 parts by weight of water per 100 parts of hydrocarbyl butanediol ethoxylate disulfate employed. The lower range of water concentration is used for compounding particulate formulations which may contain 15 parts of water per 100 parts of the hydrocarbyl butanediol ethoxylate disulfate. The upper range of water concentrations are used to prepare liquid formulations. For this use, 100 to 400 parts of water per 100 parts of hydrocarbyl butanediol ethoxylate disulfate are preferred.

The hydrocarbyl butanediol ethoxylate disulfates and their precursors as described within the scope of the present invention may be prepared by the reduction of alkenyl succinic anhydride to produce alkenyl or alkylbutanediols, ethoxylating the diols by reaction with ethylene oxide and subsequent sulfation of the ethoxylated diols. The alkenyl succinic anhydride may be produced by the familiar reaction of the condensation of maleic anhydride with an olefin.

By an alternative method, the alkenyl succinic anhydride may be reacted with an alcohol to produce the diester and then reduced to the alkyl butanediol. By controlled reduction, unsaturated portions in the alkenyl chain may be preserved.

The novel 2-hydrocarbyl-I,4-butanediol ethoxylate disulfates of the present invention may be prepared by ethoxylating and subsequently sulfating 2-hydrocarbyl- 1,4-butanediols' where the hydrocarbyl radical is an alkyl or alkenyl, as illustrated by the following: tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, eicosyl, heneicosyl, docosyl, tricosyl, tetracosyl, pentacosyl, hexacosyl, heptacosyl, octacosyl', nonacosyl, triacontyl, hentriacontyl, dotriacontyl, tritriacontyl, tetratriacontyl, pentatriacontyl, hexatriacontyl, tetradecenyl, pentadecenyl, hexadecenyl, heptadecenyl, octadecenyl, nonadecenyl, eicosenyl, heneicosenyl, docosenyl, tricosenyl, tetracosenyl, pentacosenyl, hexacosenyl, heptacosenyl, octacosenal, nonacosenyl, triacontenyl, hentriacontenyl, dotriacontenyl, tritriacontenyl, tetratriacontenyl, pentatriacontenyl and hexatriacontenyl.

Ethoxylation of the hydrocarbyl butanediol is accomplished by reacting from I to 10 moles of ethylene oxide per mole of diol in the presence of a basic catalyst. Suitable catalysts include compounds such as alkali metals, alkali metal hydroxides and metal hydrides. Reaction of the diol with ethylene oxide produces a random distribution as to the number of ethyoxylated radicals present in each of the alcohol chains.

The ethoxylated diols may be converted to disulfates by sulfation with chlorosulfonic acid, sulfur trioxide, oleum and other known sulfating agents. The sulfated product may be neutralized with aqueous basic solutions containing compounds such as hydroxides, carbonates, and oxides of the alkali metals, alkaline earth metals, ammonium and other water-soluble saltforming cationic agents.

The following examples describe the preparation of the Z-hydrocarbyl-l ,4-butanediol ethoxylate disulfates, their precursor compounds, and evaluation of the disulfates as phosphate-free detergent compositions.

EXAMPLE 1 Preparation of 2-sec-C C alkenyl succinic anhydride A mixture of 405 g. (1.5 moles) of internal olefins having from 18 to 20 carbon atoms and an average molecular weight of 270 was stirred slowly with 49 g. (0.5 mole) of maleic anhydride in a 1-liter, 3-necked, round bottom flask equipped with an explosion-proof stirrer, a drying tube condenser, and dropping funnel, and continuously flushed with nitrogen. The reaction was continued for about 7 hours at a gradually increasing temperature starting at 85C. and stopping at 212C. At the end of this time, infrared analysis showed less than 1.0 percent of maleic anhydride remaining. The mixture was transferred to a distillation flask. Unreacted olefins were removed by distillation at approximately 1 mm. pressure until about percent olefin as shown by a vapor phase chromatographic analysis. The stripped bottoms product from this distillation was then heated and filtered through Celite to give 101 g. of crude alkenyl succinic anhydride.

EXAMPLE 2 Preparation of 2-n-eicosenyl-1 ,4-butanediol A flask similar to that used in Example 1 was flushed with nitrogen and charged with 30 g. (0.8 moles) of lithium aluminum hydride. One pint (473 cc.) of tetrahydrofuran was carefully added with stirring. A solution of 189 g. (0.5 moles) of n-eicosenyl succinic anhydride in 1 pint of tetrahydrofuran was added at such a rate as to maintain reflux. Reflux was continued for three hours after addition of the anhydride. 3 g. of lithium aluminum hydride were added and heating continued for 2 hours. After standing overnight, 1 g. of lithium aluminum hydride was added and the mixture was heated at reflux for 2 additional hours. A small sample was worked up and infrared analysis showed the absence of the carbonyl band.

The reaction mixture was cooled in ice and 500 ml.

of 10 percent hydrochloric acid carefully added. The mixture was transferred to a se paratory funnel containing 2500 ml. of water and 500 ml. of diethyl ether. After shaking and separation of layers, the aqueous phase was extracted with 500 ml. of ether. The combined ether extracts were washed with 500 ml. portions of water, saturated sodium bicarbonate solution, and water. The solution was dried over anhydrous sodium sulfate and the solvent removed. The residue (llO g., percent yield) was recrystallized from hexane to give 2-n-eicosenyl-l,4-butanediol, melting point 54.555.5C. The infrared spectrum showed the presence of the double bond at 965 cm".

EXAMPLE 3 Reduction of 2-n-eicosenyl-l ,4-butanediol In a 500 ml. Fisher-Porter bottle, 40.0 g. of 2-n-eicosenyl-1,4-butanediol was dissolved in 250 ml. of absolute ethanol. To this was added 4.0 g. of palladium-on-carbon catalyst. Hydrogen was added to the bottle to give 60 psig of pressure. The contents were heated to 50C. and agitated with incremental addition of hydrogen until a total of 200 psi of hydrogen was taken up. The solution was filtered to remove the catalyst and then alcohol was removed by evaporation at 50C. to give 37 g. of a 2-n-eicosyl-l,4-butanediol having a melting point of 655C. An infrared spectrum showed the complete absence of double bonds.

EXAMPLE 4 Preparation of 2-n-hexadecyl-l,4-butanediol The procedure of Example 2 was followed, except that 27 g. (0.7 moles) of lithium aluminum hydride and a solution of 162 g. (0.5 mole) of a commercially available 2-n-hexadecyl succinic anhydride were substituted as reactants. The final residue (144 g., 91.5 percent yield) was recrystallized from hexane to give 2-n-hexadecyl-l ,4-butanediol.

Other alkyl succinic anhydrides are available commercially or may be obtained by the mild, controlled catalytic hydrogenation of the corresponding alkenyl succinic anhydride with hydrogen in the presence of a catalyst such as platinum, palladium or nickel.

EXAMPLE 5 Ethoxylation of 2-n-hexadecyl-1 ,4-butanediol A 200 ml. round-bottom flask, equipped with condenser, thermometer, heating mantle, magnetic stirrer, and sintered glass inlet was purged with nitrogen and charged with 53.5 g. (0.17 mole) of 2-n-hexadecyl-l ,4- butanediol and 0.39 g. (0.017 mole) of sodium. The temperature was raised to l00C., with stirring. When all the sodium had dissolved, 46 ml. (0.97 mole) of ethylene oxide which had previously been condensed in a receiver was vaporized into the flask as fast as could be absorbed. Samples of ethoxylated product were taken as shown in Table 1 below:

TABLE I S A M P L E ml. of Ethylene Oxide vaporized 20.1 34.5 44.2 46.0 Weight (g.) of sample taken 20.0 20.7 20.4 31.6 Molecular weight determination by OH No. 392 474 572 672 by NMR No. 384 503 604 719 Average 388 488 588 696 Average* Ethylene Oxide content (mole) 1.7 4.0 6.2 8.7

' Obtained by subtracting the molecular weight oi'the hydrocurhyl hutunediol from the average molecular weight of the ethoxylatcd product and then dividing by the molecular weight of ethylene oxide.

EXAMPLE 6 Sulfation of 2-n-hexadecyl-1,4-butanediol Ethoxylate A 500 ml. Erlenmeyer flask was charged with a solution of 6.30 g. (0.013 moles) of 2-n-hexadecyl-l,4- butanediol ethoxylate having 4.0 ethylene oxide units in 100 ml. dry ether. The solution was cooled in ice and 2.0 mlv of chlorosulfonic acid was slowly added with an eye dropper by submerging the tip below the surface of the ether. The solution was swirled and allowed to stand at room temperature for minutes. Then the solution was cooled in an ice bath and neutralized to a phenolphthalein end point with dilute sodium hydroxide. The reaction mixture was then warmed to about 50C. to remove the ether, again cooled to room temperature, transferred to a 500 ml. volumetric flask, and diluted to volume. Analysis indicated a yield of disulfate of 98.5 percent.

EXAMPLE 7 Preparation of 2-n-C and C Alkyl-l,4-butanediol Ethoxylate 61 g. (0.147 mole) of a mixture of 62 percent octacosene and 38 percent triacontene was reacted with 0.6 g. (0.16 moles) of maleic anhydride following the procedure of Example 1. The resulting alkenylsuccinic anhydride, 51.3 grams, was reduced to the diol by reaction with a total of 6.5 grams of lithium aluminum hydride, generally following the procedure of Example 2. This diol, 25 grams, was hydrogenated by the procedure of Example 3 to give 20.6 g. of an alkylbutanediol. This product was ethoxylated by the procedure of Example 5 to give three fractions of ethoxylated alkylbutanediol having an average ethylene oxide content of 2.5, 3.9, and 6.2 moles per mole of product.

EXAMPLE 8 Preparation of 2-n-C and C Alkyl-1,4-butanediol Ethoxylate Disulfate The three ethoxylates prepared in Example 7 were sulfated by the procedure of Example 6 and neutralized with sodium hydroxide.

Detergency of the compounds of the present invention has been measured by their ability to remove natural soil from cotton cloth. By this method small swatches of cloth, soiled by rubbing over face and neck, are washed with test solutions of detergents in a mini-washer, and the reflectances of the various cloths measured and compared. The results obtained are expressed as a detergent index value.

The detergent index value is obtained by comparing and correlating the reflectance value results from the test solution with the results from two defined standard solutions.

The two standard solutions are selected to represent a detergent formulation exhibiting relatively high detersive characteristics and a formulation exhibiting relatively low detersive characteristics.

By testing each soiled cotton cloth against the standardized solutions as well as the test solutions, the results can be accurately correlated. The two standard solutions were prepared from the following detergent formulation:

The standard exhibiting high-detersive characteristics was prepared by dissolving 1.5 g. of the above formulation in 1 liter of 50 ppm hard water (calcualted as two-third calcium carbonate and one-third magnesium carbonate). The low detersive standard contained 1.0 g. of the formulation dissolved in 1 liter of 180 ppm water (same basis).

The test solutions consisted of the 2-hydrocarbyl-l ,4- butanediol ethoxylate disulfates prepared as in Example 5 and formulated with other ingredients to give the following phosphate-free formulation:

EXAMPLE l0 l-lydrocarbyl Butanediol Ethoxylate Disulfate Detergent Formulation ingredient WL% Z-hydrocarbyl-l ,4-butanediol ethoxylate disulfate 25 Sodium sulfate 59 Carboxymethylcellulose l Sodium silicate 7 Water 8 Two test solutions were prepared from each formulation. The first consisted of 1 g. of formulation dissolved in 1 liter of 50 ppm hard water. The second consisted of 1.5 g. of the formulation dissolved in 1 liter of 180 ppm. hard water.

In the test procedure, one side of small white cotton swatches was uniformly soiled with natural human face and neck soil, and then cut into four 12 mm. squares. These squares were each sewn onto the center of a separate clean white cotton disc, 3.5 cm. in diameter, with the soiled side out. Each cotton disc was placed in a separate glass vessel, 4.0 cm. in diameter and 8.0 cm. tall. Then 7 ml. of a detergent solution was added,

along with ten, A-inch diameter, stainless steel balls.

One of the four glass vessels was charged with the ppm water test solution, another with 180 ppm water test solution, another with the high standard, and the last one with the low standard.

The glass vessels were stoppered, placed in a constant temperature bath at 120F., and agitated at 900 cycles/minute for 10 minutes. At the end of this time, the swatches were removed from the glass vessels and were hand-squeezed dry. They were rinsed three times for one minute each time in water of the same hardness as was used in the wash cycle. The excess water was squeezed out, and then the swatches were placed on a 6 paper towel to dry.

When dry, the soiled portions were measured for whiteness by standard photoelectric reflectance procedure. The detergency index of each test sample was then calculated, using the following formula:

Reflec. Test Samp. Reflec. Low Stand.

Reflec. High Stand. Reflec. Low Stand.

For comparison, a commercially available LAS detergent formulation was measured by the detergency index rating. The formulation was as follows:

EXAMPLE ll LAS Detergent Formulation Without Phosphate Ingredient Wt.%

LAS 25 Sodium Sulfate 59 Sodium silicate 7 Carboxymethylcellulose 1 Water 8 A 0.1 percent by weight concentration in 50 ppm hard water gave a detergency index value of 0.74 and a 0.15 percent by weight concentration in 180 ppm water gave a value of 0.64.

Detergency test results obtained on a variety of butanediol ethoxylate disulfates in phosphate-free formulations are given in Table II. From these data, it is quite evident that the butanediol ethoxylate disulfates are not only superior in detergency to non-phosphate built LAS detergents, but in many cases superior in detergency to LAS phosphate formulations.

TABLE II sion, without departing from the spirit or scope of the following claims.

What is claimed is: 1. A compound of the formula CH CH 0 (CI-I CH O) -SO M 0 (CH CI-l 0)y-S0 M CH CH wherein M is hydrogen, or an alkali metal, alkaline earth metal, or ammonium cation; x and y are independent whole numbers, the sum of which ranges from 1 to 10; R is an alkyl or alkenyl radical having from 14 to 36 carbon atoms and represented by the formula R -CH- wherein R and R are hydrogen, alkyl or alkenyl radicals of 0 to carbon atoms, and the sum of carbon atoms in R and R is from 13 to 35.

2. A compound as in claim 1, wherein M is selected from the group consisting of sodium, potassium, ammonium, calcium and magnesium.

3. A compound as in claim 2, wherein R is hydrogen DETERGENCY Z-n-HYDROCARBYL BUTANEDIOL ETHOXYLATE DISULFATES Detergency Index See footnote in Table I All of the above values represent detergents formulated in accordance with Example 10 except for Examples 9 and 11.

As will be evident to those skilled in the art, various modifications of the present invention can be made or followed in light of the foregoing disclosure and discusand R is selected from the group consisting of nhexadecyl, n-octadecyl, n-nonadecyl, n-eicosyl, and ndocosyl.

4. A compound as in claim 2, wherein the sum of x and y ranges from 2 to 6. 

1. A COMPOUND OF THE FORMULA: WHEREIN R2 AND R3 ARE HYDROGEN, ALKENYL RADICALS OF 0 TO 35 CARBON ATOMS, AND THE SUM OF CARBON ATOMS IN R2 AND R3 IS FROM 13 TO 35:
 2. A compound as in claim 1, wherein M is selected from the group consisting of sodium, potassium, ammonium, calcium and magnesium.
 3. A compound as in claim 2, wherein R2 is hydrogen and R3 is selected from the group consisting of n-hexadecyl, n-octadecyl, n-nonadecyl, n-eicosyl, and n-docosyl.
 4. A compound as in claim 2, wherein the sum of x and y ranges from 2 to
 6. 